超级玛丽

\(f(i) = f(i + 1) + f(i + 2) ,st[i] = 0;\\ f(i) = 0, st[i] = 1;\)

#include<iostream>
using namespace std;

const int N = 50;
int n, m;
int st[N], f[N];

int main(){
    cin >> n >> m;
    
    while(m --){
        int t;
        cin >> t;
        st[t] = 1;
    }
    
    f[n] = 1;
    
    for(int i = n - 1; i >= 0; i --){
        f[i] = f[i + 1];
        if(st[i]) f[i] = 0;
        else if(i + 2 <= n) f[i] += f[i + 2];
    }
    
    cout << f[1];
}